package com.vf.admin.utils.hongbao;

import java.util.Random;

/**
 * 红包工具类
 */
public class HongBaoUtils {

    public static double hongbao(int count, double amount, double singleMin, double singleMax) {
//        if (amount > singleMax || amount < singleMin) {
//            throw new UnsupportedOperationException(String.format("金额不能大于%s,不能小于%s", singleMax, singleMin));
//        }
//        if (count * singleMin > amount) {
//            throw new UnsupportedOperationException(String.format("金额不足够发%s个红包", count));
//        }

        if (count == 1) {
            return (double) Math.round(amount * 100) / 100;//剩余最后一个
        }

        double min = 0.01;//当前红包的最小金额
        double max = amount / count * 2;//当前红包的最大金额
        double money = new Random().nextDouble() * max;//金额
        money = money <= min ? min : Math.floor(money * 100) / 100;//特殊处理,保留2位小数，四舍五入
        return money;
    }


    public static void main(String[] args) {
        int count = 1;//个数
        double amount = 99;//金额
        double singleMin = 0.01;//单个红包最小金额
        double singleMax = 99;//单个红包最大金额
        double money = 0;
        double zongmoney = 0;

        if (amount > singleMax || amount < singleMin) {
            System.out.println("金额不能大于"+singleMax+"不能小于"+singleMin);
        }
        if (count * singleMin > amount) {
            System.out.println("金额不足够发"+count+"个红包,");
        }

        for (int i = 0, len = count; i < len; i++) {//模拟'count'个人抢红包，
            money = HongBaoUtils.hongbao(count--, amount -= money, singleMin, singleMax);
            System.out.println(String.format("第%s个人抢到红包:%s", i + 1, money));
            zongmoney += money;
        }
        System.out.println(zongmoney);
    }



}
